Hi//
I have a relatively new iPhone 5 (CDMA version) running on T Mobile's network. Generally very happy with it. When I'm solidly in a 3G cell's coverage the bandwidth is very good (say 6 megs down and 1.5 megs up). But here's the rub. Should also mention that I've switched to reading dB rather than 'bars' for signal strength. This comes from the 'Field Test' routine. (*3001#12345#* Hold down the power key and when the power off slider shows up hold down the Home button until it exits Field Test. Your default signal strength is now in dB.)

I can be sitting in a cell that shows -75dB and 3G (basically on top of the base station) and have the reading switch from 3G to E (EDGE) with exactly the same signal strength. EDGE is very ratty. Does anyone know what's going on here??
o Will the iPhone automatically switch to the technology that appears to have the higher signal and select EDGE over 3G? Does it prefer 2G over 3G? Could this be a firmware issue?
o Could this be a hardware problem? Any thoughts?
o My wife has an identical iPhone on the same network. I can place them side by side and see -75dB on one and -130dB on the other. This is a huge difference. Has anyone else experienced this?

I'd like to know if there's a way to 'tell' the iPhone to only connect to 3G, or at least to prefer 3G until the signal strength drops below a certain level. Then, if I'm in a cell with 3G I'll be able to use it. Personally I'd rather have 3G at -100dB than EDGE at -75dB.

I have the same issue with my iPhone. I gave my sister my hand me down 4S in January for her birthday which she promptly activated on T-Mobile. T-Mobile promised that our area had been refarmed and that the iPhone 4S would experience faster download speeds than AT&T offered. That was true for about the first hour. Then the lovely 4G symbol disappeared and turned to an E. When T-Mobile pushed out their carrier update her 4G symbol returned for the day, only to be replaced again by an E. The only time she gets 4G is in the first hour or so after powering on her device.

Earlier this week I replaced the AT&T Sim in my iPhone 5 with a T-Mobile Sim and almost fell over when it instantly connected to LTE service (Sacramento, CA). About a half hour later it switched to 4G and within 45 seconds it was an E. Every network settings reset got me another half hour of LTE, and even the T-Mobile reps confirmed my house is "in an excellent LTE coverage area." It seems like once the iPhone gets ahold of an EDGE signal it hangs on for dear life. If I have an LTE signal and turn on my wifi for more than 5 minutes it is nearly a guarantee that I will have EDGE service after the wifi is disconnected.

When I owned the AT&T 4S that she now uses on T-Mobile I almost never saw the 4G symbol change during the course of the day and would occasionally receive download speeds up to 7 Mbps. My iPhone 5 is on LTE 95% of the time (I split my time between Sacramento and San Francisco, so in the freeway farmlands between the cities it will occasionally drop to 4G). I don't know why the iPhone 4S and 5 are so keen on sticking to EDGE frequencies, but it seems like a widespread issue. I've discussed the issue with quite a few reps who confirm it affects the Galaxy Note II, Galaxy S4, iPhone 5 and iPhone 4S (some, but not all. Some of those models get perfect 4G or LTE service without a hitch.)

It's weird, but it's worth it. I was paying $65/mo. on AT&T for 3 gigabytes of data, but I could regularly see 45+ Mbps down. My Nexus 4 on T-Mobile averaged about 15 Mbps down, and my iPhone 5 gets 20-22 Mbps down on LTE but the $30 per month plan with 5 gigabytes of data make the EDGE issue much less frustrating to me personally. On a side note I have noticed that my iPhone 5 battery drains SIGNIFICANTLY faster when the T-Mobile SIM is inserted. I have a personal record of 31 hours between charges on the iPhone 5 with the AT&T sim, but it seems like with the T-Mobile sim in the phone wants to be juiced up twice a day. Maybe I'm just imagining things?

Hi//
I have a relatively new iPhone 5 (CDMA version) running on T Mobile's network. Generally very happy with it. When I'm solidly in a 3G cell's coverage the bandwidth is very good (say 6 megs down and 1.5 megs up). But here's the rub. Should also mention that I've switched to reading dB rather than 'bars' for signal strength. This comes from the 'Field Test' routine. (*3001#12345#* Hold down the power key and when the power off slider shows up hold down the Home button until it exits Field Test. Your default signal strength is now in dB.)

I can be sitting in a cell that shows -75dB and 3G (basically on top of the base station) and have the reading switch from 3G to E (EDGE) with exactly the same signal strength. EDGE is very ratty. Does anyone know what's going on here??
o Will the iPhone automatically switch to the technology that appears to have the higher signal and select EDGE over 3G? Does it prefer 2G over 3G? Could this be a firmware issue?
o Could this be a hardware problem? Any thoughts?
o My wife has an identical iPhone on the same network. I can place them side by side and see -75dB on one and -130dB on the other. This is a huge difference. Has anyone else experienced this?

I'd like to know if there's a way to 'tell' the iPhone to only connect to 3G, or at least to prefer 3G until the signal strength drops below a certain level. Then, if I'm in a cell with 3G I'll be able to use it. Personally I'd rather have 3G at -100dB than EDGE at -75dB.

Thanks,

Bob

Could be that the CDMA version is not native to T-Mobile. There are lots of threads on here about how phones work best with their native carriers.